At slaughterhouses tenderloins are normally removed from half-carcasses by partly cutting free the tenderloin with a hand-held butcher knife or a circular knife with a spinning blade and afterwards grapping the tenderloin with a hand and pulling it away from the half-carcass. During this process an abattoir worker position a handheld power-operated rotary knife in the area of the head of the tenderloin, cut free a part of the tenderloin and removes the rotary knife by moving it back along the part of the tenderloin which has just been cut free. With the free hand the tenderloin is pulled free. This is a process putting a high stress on the butchers due to continuously doing the same movements and using forces to pull free the tenderloins.
Power-operated rotary knives are used for different purposes at abattoirs and other food processing facilities. These knives usually comprise a handle and a blade housing which supports an annular knife blade. The knife blade is driven about its central axis relatively to the blade housing by a motor via a gear train. These knives are not strong enough for a tool for automatic removal of meat pieces fush as tenderloins.
U.S. Pat. No. 5,664,332 (Bettcher Industries) describes a power-operated hand held slicing knife with a handle assembly, a ring-like blade housing, a ring-formed knife blade, a blade drive transmission, a depth gauge member and a material directing cover. The knife blade is constructed such that it projects radially inwardly. Such a hand knife is for trimming meat by slicing away layers of e.g. fat with a thickness determined by the depth gauge member. Such slicing knifes are not suitable for removing entire meat pieces such as tenderloins as the cover encircles the upper part of the knife which together with the depth gauge member prevent larger meat pieces to be cut away, furthermore the inwardly projecting knife blade is not suitable to cut out larger meat pieces.
EP1937077 (Teknologisk Institut) describes an apparatus and a method for cutting free at least a part of a tenderloin in a suspended half-carcass. The apparatus comprises a cutting device having a sharp edge curving transversely to the edge, and a moving device for the cutting device for moving the cutting device with the sharp edge foremost during cutting free of at least a part of the tenderloin in a half-carcass. This cutting device is not as easy to steer as required for removing tenderloins.
U.S. Pat. No. 7,285,040 (Maja Maschinenfabrik Hermann Schill) describes a device and an method for de-rinding or trimming a piece of meat, where the device includes an industrial robot with a manipulator arm, a sensor system which detects the part that is to be separated from the meat piece and a cutting tool which separates the detected part from the meat piece. The cutting tool is a knife with a circular rotating blade with a cutting depth setting. The parts of the meat piece to be removed are remnants of meat or fat which remain on the surface during the mechanical de-rinding. The manipulator arm equipped with a trimmer moves along the surface and separates identified remnants from the meat piece. This system is for removing remnants of meat or fat and is not suitable to remove meat pieces such as tenderloins, as the process is different in that when removing remnants this need not be done by taking care of both the removed part and the underlying meat, whereas when removing tenderloins it is important to obtain as entire a meat piece as possible as deviation from the standard reduces the quality and therefore the price of the product.
A more flexible and still strong meat piece removing tool and system is invented and described herein. The meat piece removing tool may be used as a hand-held device or in an automatic process.